1. Northwest Research Institute of Engineering investigations and design, Xi'an 710003, China 2. Institute of Geosciences and Info Physics, Central South University, Changsha 410083, China 3. Shaanxi Energy Institute, Xianyang 712000, China
The industrial interference in Tongchuan City survey area is strong, where stratigraphic sedimentary types are complex, the lithology varies remarkably, the terrain is fluctuating, and the gully and the ridge are crisscross. The audiomagnetotelluric method (AMT) is characterized by a single point of measurement, great detection depth, high horizontal resolution and other technical advantages. At the same time, the magnetotelluric remote reference technology can suppress random noise, restore the "dead band" data, and improve the magnetotelluric data quality. In order to study the application effect of magnetotelluric remote reference technology in the urban strong electromagnetic interference environment, the authors constructed an audio magnetotelluric profile in Tongchuan investigation area. The nonlinear conjugate gradient (NLCG) method was used to carry out the data inversion and data analysis. The results show that the application of remote reference technology to the processing of magnetotelluric data can effectively improve the quality of noise data, and the inversion results are more consistent with the geological data.
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